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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 17 |
| 5 | 46 |
| 6 | 114 |
| 7 | 262 |
| 8 | 574 |
| 9 | 1427 |
| 10 | 2927 |
| 11 | 6603 |
| 12 | 14404 |
| 13 | 30565 |
| 14 | 63613 |
| 15 | 138813 |
| 16 | 280318 |
| 17 | 587475 |
| 18 | 1218642 |
| 19 | 2483850 |
| 20 | 5029611 |
| 21 | 10412477 |
| 22 | 20733046 |
| 23 | 42016631 |
| 24 | 84910771 |
| 25 | 169447050 |
| 26 | 337521488 |
| 27 | 680231390 |
| 28 | 1340806837 |
| 29 | 2667729672 |
| 30 | 5306731496 |
| 31 | 10458274889 |
| 32 | 20608397551 |
[1,1,3,9,17,46,114,262,574,1427,2927,6603,14404, 30565,63613,138813,280318,587475,1218642,2483850, 5029611,10412477,20733046,42016631,84910771, 169447050,337521488,680231390,1340806837, 2667729672,5306731496,10458274889,20608397551] |